Apply by doing:
cd /usr/src
patch -p0 < 005_ptrace.patch
Then build and install a new kernel.
Index: sys/compat/hpux/hpux_compat.c
===================================================================
RCS file: /cvs/src/sys/compat/hpux/hpux_compat.c,v
retrieving revision 1.30
retrieving revision 1.30.6.1
diff -u -p -r1.30 -r1.30.6.1
--- sys/compat/hpux/hpux_compat.c 1 Nov 2008 05:59:21 -0000 1.30
+++ sys/compat/hpux/hpux_compat.c 29 Jan 2010 21:33:13 -0000 1.30.6.1
@@ -1,4 +1,4 @@
-/* $OpenBSD: hpux_compat.c,v 1.30 2008/11/01 05:59:21 deraadt Exp $ */
+/* $OpenBSD: hpux_compat.c,v 1.30.6.1 2010/01/29 21:33:13 sthen Exp $ */
/* $NetBSD: hpux_compat.c,v 1.35 1997/05/08 16:19:48 mycroft Exp $ */
/*
@@ -966,7 +966,7 @@ hpux_sys_getpgrp2(cp, v, retval)
if (p == 0)
return (ESRCH);
if (cp->p_ucred->cr_uid && p->p_ucred->cr_uid != cp->p_ucred->cr_uid &&
- !inferior(p))
+ !inferior(p, cp))
return (EPERM);
*retval = p->p_pgid;
return (0);
Index: sys/sys/proc.h
===================================================================
RCS file: /cvs/src/sys/sys/proc.h,v
retrieving revision 1.119
retrieving revision 1.119.4.1
diff -u -p -r1.119 -r1.119.4.1
--- sys/sys/proc.h 5 Jun 2009 00:30:05 -0000 1.119
+++ sys/sys/proc.h 29 Jan 2010 21:33:13 -0000 1.119.4.1
@@ -1,4 +1,4 @@
-/* $OpenBSD: proc.h,v 1.119 2009/06/05 00:30:05 guenther Exp $ */
+/* $OpenBSD: proc.h,v 1.119.4.1 2010/01/29 21:33:13 sthen Exp $ */
/* $NetBSD: proc.h,v 1.44 1996/04/22 01:23:21 christos Exp $ */
/*-
@@ -417,7 +417,7 @@ int chgproccnt(uid_t uid, int diff);
int enterpgrp(struct proc *p, pid_t pgid, struct pgrp *newpgrp,
struct session *newsess);
void fixjobc(struct proc *p, struct pgrp *pgrp, int entering);
-int inferior(struct proc *p);
+int inferior(struct proc *, struct proc *);
int leavepgrp(struct proc *p);
void yield(void);
void preempt(struct proc *);
Index: sys/kern/kern_proc.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_proc.c,v
retrieving revision 1.40
retrieving revision 1.40.4.1
diff -u -p -r1.40 -r1.40.4.1
--- sys/kern/kern_proc.c 15 Apr 2009 10:47:46 -0000 1.40
+++ sys/kern/kern_proc.c 29 Jan 2010 21:33:13 -0000 1.40.4.1
@@ -1,4 +1,4 @@
-/* $OpenBSD: kern_proc.c,v 1.40 2009/04/15 10:47:46 art Exp $ */
+/* $OpenBSD: kern_proc.c,v 1.40.4.1 2010/01/29 21:33:13 sthen Exp $ */
/* $NetBSD: kern_proc.c,v 1.14 1996/02/09 18:59:41 christos Exp $ */
/*
@@ -151,14 +151,14 @@ chgproccnt(uid_t uid, int diff)
}
/*
- * Is p an inferior of the current process?
+ * Is p an inferior of parent?
*/
int
-inferior(struct proc *p)
+inferior(struct proc *p, struct proc *parent)
{
- for (; p != curproc; p = p->p_pptr)
- if (p->p_pid == 0)
+ for (; p != parent; p = p->p_pptr)
+ if (p->p_pid == 0 || p->p_pid == 1)
return (0);
return (1);
}
Index: sys/kern/kern_prot.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_prot.c,v
retrieving revision 1.39
retrieving revision 1.39.4.1
diff -u -p -r1.39 -r1.39.4.1
--- sys/kern/kern_prot.c 2 Jun 2009 20:03:59 -0000 1.39
+++ sys/kern/kern_prot.c 29 Jan 2010 21:33:13 -0000 1.39.4.1
@@ -1,4 +1,4 @@
-/* $OpenBSD: kern_prot.c,v 1.39 2009/06/02 20:03:59 guenther Exp $ */
+/* $OpenBSD: kern_prot.c,v 1.39.4.1 2010/01/29 21:33:13 sthen Exp $ */
/* $NetBSD: kern_prot.c,v 1.33 1996/02/09 18:59:42 christos Exp $ */
/*
@@ -282,7 +282,7 @@ sys_setpgid(struct proc *curp, void *v,
newpgrp = pool_get(&pgrp_pool, PR_WAITOK);
if (pid != 0 && pid != curp->p_pid) {
- if ((targp = pfind(pid)) == 0 || !inferior(targp)) {
+ if ((targp = pfind(pid)) == 0 || !inferior(targp, curp)) {
error = ESRCH;
goto out;
}
Index: sys/kern/sys_process.c
===================================================================
RCS file: /cvs/src/sys/kern/sys_process.c,v
retrieving revision 1.43
retrieving revision 1.43.6.1
diff -u -p -r1.43 -r1.43.6.1
--- sys/kern/sys_process.c 31 Oct 2008 17:29:51 -0000 1.43
+++ sys/kern/sys_process.c 29 Jan 2010 21:33:13 -0000 1.43.6.1
@@ -1,4 +1,4 @@
-/* $OpenBSD: sys_process.c,v 1.43 2008/10/31 17:29:51 deraadt Exp $ */
+/* $OpenBSD: sys_process.c,v 1.43.6.1 2010/01/29 21:33:13 sthen Exp $ */
/* $NetBSD: sys_process.c,v 1.55 1996/05/15 06:17:47 tls Exp $ */
/*-
@@ -167,6 +167,14 @@ sys_ptrace(struct proc *p, void *v, regi
*/
if ((t->p_pid == 1) && (securelevel > -1))
return (EPERM);
+
+ /*
+ * (6) it's an ancestor of the current process and
+ * not init (because that would create a loop in
+ * the process graph).
+ */
+ if (t->p_pid != 1 && inferior(p, t))
+ return (EINVAL);
break;
case PT_READ_I: